The present invention relates to a method for converting a three-party telecommunications connection, which is switched via a public communications network, between two subscriber lines and a further subscriber line or between two subscriber lines and an operator's position, into a two-party telecommunications connection between the two subscriber lines. The three-party telecommunications connection is routed here via the telecommunications switching office to which the further subscriber line or the operator's position is connected.
The conversion of a three-party telecommunications connection into a two-party telecommunications connection is carried out in a known fashion by releasing the section of the three-party telecommunications connection between the further subscriber line or the operator's position and its telecommunications switching office. The known method is applied, for example, in the case in which a subscriber of the telecommunications network, for example a customer of a bank, wishes to set up a connection to an employee of a bank at a bank branch. The connection setup to the employee of the bank is processed, for example, as follows:
The customer of the bank sets up a connection from his/her subscriber terminal to his/her local switching office; for example in Munich. From this local switching office, a connection is switched to a further telecommunications switching office, for example in Hamburg, on the basis of a call divert which is set up in the local switching office, wherein a number of operators' positions, for example of a call center, are connected to the further telecommunications switching office. The connection is finally switched from the telecommunications switching office in Hamburg to an operator's position.
A switching operator at the operator's position then searches for the call number of the employee of the bank requested by the customer of the bank and initiates a connection setup from the telecommunications switching office in Hamburg to the same local switching office in Munich or to another local switching office to which the individual subscriber lines of the employees of the bank are connected. From this local switching office, the connection is finally switched through to the requested employee of the bank. After a successful connection setup from the customer of the bank to the requested employee of the bank, the switching operator brings about the conversion into a two-party telecommunications connection, wherein the operator's position is released from the connection.
The known method is also applied to the case of a multiparty service. For this purpose, the customer of the bank calls, for example, an employee of the bank at a banking service center in Hamburg. This employee of the bank then establishes a three-party multiparty service connection to a further employee of a bank branch; for example, in Munich. After a certain period of time during the call, the employee of the banking service center is released from the three-party multi-party service connection, and in his/her local switching office in Hamburg brings about the interconnection of the section of the connection between the customer of the bank and the telecommunications switching office in Hamburg and the section of the connection between the telecommunications switching office in Hamburg and the employee of the bank branch in Munich. In this way, a two-party connection is maintained between the customer of the bank and the employee of the bank branch in Munich.
In the known method, there is, however, the disadvantage for the bank that when there is a call divert to an operator's station, for example in Hamburg, the bank has to pay for the existing telecommunications connection between the local switching office in Munich and the telecommunications switching office in Hamburg despite the fact that once the operator's position has been released from the three-party connection there is then only a call connection to the employee at the Munich branch of the bank. If there is a call transfer by the employee of the banking service center, the customer of the bank has to pay the tolls for the long-distance connections between his/her local switching office and the telecommunications switching office in Hamburg as well as between the remote switching office in Hamburg and the local switching office, for example in Munich, which is responsible for the bank branch.
Furthermore, additional resources, for example in the form of channel assignments on the connection lines and/or for the switching operation, in the telecommunications switching office itself are used up for the long-distance connections via the telecommunications switching office in Hamburg.
A method for carrying out a connection setup for a call diversion or connection forwarding in a communications network is already known (DE 196 53 622 A1). Here, when there is a call from a subscriber's station of a first communications system to a subscriber's station which is assigned to a second communications system and for which a call diversion or at which a call forwarding to a subscriber's station of a third communications system is set up or brought about, a connection to the third communications system is first set up via the second communications system. An equivalent path inquiry is then transmitted from this third communications system to the calling, first communications system, in response to which the first communications system determines an alternative connection path (bypassing the second communications system) and causes the third communications system to change over to the alternative connection path. However, such a procedure is not readily suitable for converting the three-party telecommunications connection described above into a two-party telecommunications connection.
An object of the present invention is, therefore, to configure a method of the type mentioned at the beginning to the effect that the disadvantages explained above are eliminated.